Retort



FLOYD J. METEG-EB, OF new YQRK, 13'. SK,

ASSIGNOB To an. ucrroiu a OF NEW YORK, N. Y., A ORPORATIOH 0F YfiBK.

Patented Jnly 18, 1922.,

newer.

11 22,878. Specification of Letters Patent.

No Drawing.

To all whom it may concern:

Be it known that I, Fnoro J. iikrzsnn, a citizen of the United States, residing in New York, county of New York, State of New York, have invented certain new and useful Improvements in Retorts, of which the following is a specification.

In many manufacturing operations where retorts, furnaces and the like are subjected to a high temperature it is desirable to employ iron or other similar relatively cheap and plentiful metal as the retort or furnace material. For example, in the manufacture of coal gas, oil gases and in certain processes employed to effect the fixation of atmospheric nitrogen and in numerous other processes not necessary to be mentioned, iron retorts or furnaces would be highly desirable were it not for the fact that the corrosion or oxidation of the retort or furnace is quite rapid at the rather high temperatures required in these processes. The rapid deterioration and destruction of retorts or fun naces consisting of iron or other similar metal involves in many cases a prohibitive maintenance cost and a conseguentor necessary elimination of iron as a furnace material for such purposes.

I have discovered that by property treating the iron; that is, by providing it with a coating of material which is practically unaffected by or which oifers substantial resistance to the corrosive or oxidizing action of the gases which are enerated in a retort or furnace, I am enab 'ed to protect such iron or other similar suitable metal to a very great extent if not entirely against the corrosive action of such gases. As a result the life of the retort or furnace is greatly prolonged, thereby reducing the lip-keep expense of'the same to a point at which the use of iron and such other similar metals as may be found to be practicably suitable for retort or furnace material becomes come mercially feasible.

My invention comprehends theidea that all parts of the surface of the retort or furnace with-which the retort or furnace gases contact shall be coated over in oi proper manner with a metal or metal alloy which olfers substantial resistance to the corrosive or oxidizing action of theretort once gases- 1 I have found that an alloy of nickel and chromium inthe proper proportions with or Application filed @ctoher 11, 1917. Serial 3:30. 195,951.

construction of retorts or furnaces to be en,

ployed for the purposes previously stated with a coating of metal which will Oder substantial resistance to the corrosive action of the retort or furnace gases, such coating to be applied directly to and intimately combined with the portions of the surface of the iron of the retort which, but for the presence of the coating, would he acted upon by the said gases.

l have. discovered that an alloy of nichei and chromium in the proper proportions with or without the addition of smaller quantities of other metals serves very weli as a protective coating for an iron retort or furnace. Such alloy may consist of nickel and from 10 to 15%chrominm,-the variations in the latter depending upon the amount of impurities which may he present such, for example, as iron, manganese and carbon. 1 have also found that an alloy consisting of approximately" 50 to $0% of nicirel, 10 to 20% of chromium and 10 to 30% of iron may be employed. Such aiioys as the foregoing ofier substantial resistance to the corrosive or oxidizing action of the retort or furnace gases.

I propose to form the coating of the character above described upon the iron or similar metal of the retort by projecting the coating material in the form of very finely divided or atomic-like particles with great force against the surface to be coated. 'lhese particles may he in a molten state and sprayed by means of any known form of atomizing device against the surface to he coated or the said coating metal may he converted in any suitable manner into fine particles and propelled with such speed and force against the surface to be coatedthat upon the mrih'ng of the particles ainst the surface to he coated the finetic energy is converted partly-into mechanical work and partly into heat so that the finely dividedparticles are not onl intimately coinhined and connected with t e surface portions of the metal of the retort to be coated but the particles themselves are overlapped, interroe mingled, and welded together so that a uniform, dense and compact coating upon the surface of the iron, retort is produced.

This coating in efifect practically is integral with the iron or other metal of which the retort is constructed. The said coating,- together with the relatively heavy sheet metal to which it is applied may be regarded and considered as a single integral metallic sheet.

The combining of the minute particles of an alloy comprising nickel and chromium with each other and with the iron or other similer metal or" the retort provides a novel article of commerce; viz, a retort comprising or consisting of a base metal portion, es iron, and an integral coating of en alloy com rising nickel and chromium as stated. uch an alloy having the characteristic of odoring substantial resistance to the corrosive end oxidizing action of the retort or furnace gases and its application as a coating to the required portionor portions of the surface of an iron retort or furnace being feasible ll am enabled to employ commercially retcrtsor furnaces made of iron or en ers other. similar inetel which is readily corroded and oxidized by the notion of the retort or furnace gases.

1 claim 1. A retort adapted for use in the manufacture of alkali metal cyanide and to be consisting of a base metal alloy which resists the oxidizing action of said gases.

2. A retort adapted for use in the manufacture of alkali metal cyanide and to be subjected to the action of oxidizing gases at high temperature, the retort comprising a body of ferrous metal which is corrodible by said gases and a protecting skin coating applied to the outer surface of the body and consisting of e. nickel-chromium alloy which resists the oxidizing action of said gases.

In testimony that I claim the foregoing as my invention, l have hereunto signed my name this 9 day of @ctober, A. D. 1917.

' 'FLOYD J METZGER. 

